In order to study the influence on the electric connector inherent frequency, maximum stress and contact clearance of the different structure parameters of contact element, by the orthogonal experiment method, a modal analysis and random vibration analysis to electrical connector were conducted, and the optimal level combination was obtained. The natural frequency, the maximum stress and contact gap value of the electric connector of the electrical connector were compared before and after optimization. At last, using the Miner linear cumulative damage theory, the fatigue life of the electric connector was predicted. The results indicate that, the maximum stress value and the contact gap of radial load of the electric connector are bigger than axial loading. The width of spring crown has the biggest influence on firstorder natural frequency, the length of spring crown has the biggest influence on maximum stress, and the thickness of spring crown has the biggest influence on contact element clearance. By optimizing the structure size of the crown spring, the contact clearance can reduce when the electric connector contact by vibration load, the maximum stress value will also fell sharply and the firstorder natural frequency values has rise obviously. The electric connector has no fatigue failure before and after optimization, the overall damage value after optimization is declined larger compared with before optimization, and the optimized structure size can greatly enhance the fatigue life of electric connector.